AB1032 PREDICTORS OF INCREASING NUMBER OF FRACTURES IN A LARGE COHORT OF PATIENTS PRESENTING FOR DUAL-ENERGY X-RAY ABSORPTIOMETRY SCAN
Authors: Z. Sultan, M. Bukhari
Journal: Annals of the Rheumatic Diseases (2022)

Background Osteoporosis has been described as a global epidemic(1), it is the most common disease affecting bones (2). Incidence of osteoporosis is estimated to double by 2034(2) and osteoporotic fractures are expected to cost the US healthcare system around $50 billion by 2040(1), this is more than that for either chronic lung disease, breast cancer, diabetes, or stroke (1). Thus, it is vital to define the risk factors and characteristics associated with fractures to aid early prophylaxis. Objectives 1.Identify risk factors and predictors associated with fractures. Methods 31546 patients presented to a district general hospital in North West England for dual energy X-ray absorptiometry scan between 1996 and 2017. Demographics, risk factors and incidence of fractures were recorded. This data was retrospectively analysed to identify patients who had sustained at least one fracture. Patients were divided into three groups – group 1 had one fracture, group 2 had two fractures and group 3 had three or more fractures. STATA was used for statistical analysis. One way ANOVA with a Tukey post-hoc test and chi-squared test were used to compare the three groups. Results 11839 patients were identified to have sustained at least one fracture, this included 9993 females and 1846 males (Table 1). Group 1 contained 9390, group 2 contained 2050 and group 3 contained 399 patients. A statistically significant increase in the proportion of females within in each group was observed as the number of fractures increased (chi squared=13.99, p=0.001). There was a significant reduction in average height, weight and BMI between the 3 fracture groups with an increasing number of fractures (f(2)=31.67, p=0.0000, f(2)=23.71, p=0.0000 and f(2)=8.14, p=0.0003 respectively). Group 3 had the oldest mean age and group 1 the youngest (f(2)=44.36, p=0.0000). A significant reduction in fat percentage of the spine was identified as number of fractures increased (f(2)=4.92, p=0.0073). A significant increase in the proportion of patients with a history of smoking and alcohol excess within each group was observed as number of fractures increased (chi squared=7.48, p=0.024 and chi squared = 23.12, p=0.000 respectively). Mean T score in the lumbar spine, total femur and femoral neck were significantly lower between the 3 fracture groups with increasing fractures (f(2)=60.54, p=0.0000, f(2)=156.44, p=0.0000 and f(2)=115.86, p=0.0000 respectively). Table 1. No. of fractures vs patient characteristics. Characteristic 1 Fracture 2 Fractures ≥3 Fractures Mean height, cm (SD) 161.49 (8.33) 160.45 (8.45) 158.70 (8.73) Mean weight, kg (SD) 70.77 (15.93) 69.70 (15.42) 65.51 (14.69) Mean BMI, kg/m2 (SD) 27.09 (5.54) 27.01 (5.27) 25.96 (5.22) Mean age (SD) 67.45 (11.85) 69.76 (11.76) 70.84 (11.62) Mean spine fat, % (SD) 30.61 (10.92) 30.58 (10.52) 28.87 (11.36) Mean lumbar spine T-score (SD) -1.23 (1.60) -1.55 (1.52) -1.86 (1.47) Mean total femur T-score (SD) -1.28 (1.22) -1.69 (1.15) -2.07 (1.13) Mean femoral neck T-score (SD) -1.47 (1.10) -1.80 (1.00) -2.04 (0.97) Proportion of females (%) 83.84 86.00 89.47 Proportion of pts with smoking history (%) 37.42 39.41 43.11 Proportion of pts with excess alcohol history (%) 7.96 9.90 13.78 Conclusion Some important risk factors and characteristics in patients sustaining fractures have been identified. Increased height, weight and BMI are associated with sustaining fewer fractures. Increasing age is associated with having sustained more fractures, in line with what is expected with the reducing T-scores and the ageing process. A reduced spine fat percentage is associated with higher number of fractures suggesting that fat provides a protective effect to bone. Finally, a history of smoking and excess alcohol consumption are shown to be important risk factors in sustaining increasing numbers of fractures. References [1]Sözen T, Özişik L, Başaran NÇ. An overview and management of osteoporosis. Eur J Rheumatol . 2017;4(1):46-56 [2]Coughlan T, Dockery F. Osteoporosis and fracture risk in older people. Clin Med (Lond). 2014;14(2):187-191 Disclosure of Interests None declared